Embodiments described herein relate generally to delivering a fluid to a patient, and more particularly to devices and methods for delivering a parenteral fluid to a patient with reduced contamination from microbes or other contaminants exterior to the body and/or the fluid source, such as dermally residing microbes.
Human skin is normally habituated in variable small amounts by certain bacteria such as coagulase-negative Staphylococcus species, Proprionobacterium acnes, Micrococcus species, Streptococci Viridans group, Corynebacterium species, and Bacillus species. These bacteria for the most part live in a symbiotic relationship with human skin but in some circumstances can give rise to serious infections in the blood stream known as septicemia. Septicemia due to these skin residing organisms is most often associated with an internal nidus of bacterial growth at the site of injured tissue, for example a damaged, scarred heart valve, or a foreign body (often an artificial joint, vessel, or valve). Furthermore, there are predisposing factors to these infections such as malignancy, immunosuppression, diabetes mellitus, obesity, rheumatoid arthritis, psoriasis, and advanced age. In some instances, these infections can cause serious illness and/or death. Moreover, these infections can be very expensive and difficult to treat and often can be associated with medical related legal issues.
In general medical practice, blood is drawn from veins (phlebotomy) for two main purposes; (1) donor blood in volumes of approximately 500 mL is obtained for the treatment of anemia, deficient blood clotting factors including platelets and other medical conditions; and (2) smaller volumes (e.g., from a few drops to 10 mL or more) of blood are obtained for testing purposes. In each case, whether for donor or testing specimens, a fluid communicator (e.g., catheter, cannula, needle, etc.) is used to penetrate and enter a vein (known as venipuncture) enabling withdrawing of blood into a tube or vessel apparatus in the desired amounts for handling, transport, storage and/or other purposes. The site of venipuncture, most commonly the antecubital fossa, is prepared by cleansing with antiseptics to prevent the growth of skin residing bacteria in blood withdrawn from the vein. It has been shown venipuncture needles dislodge fragments of skin including hair and sweat gland structures as well as subcutaneous fat and other adnexal structures not completely sterilized by skin surface antisepsis. These skin fragments can cause septicemia in recipients of donor blood products, false positive blood culture tests and other undesirable outcomes. Furthermore, methods, procedures and devices are in use, which divert the initial portion of venipuncture blood enabling exclusion of these skin fragments from the venipuncture specimen in order to prevent septicemia in recipients of donor blood products, false positive blood culture tests and other undesirable outcomes.
Venipuncture is also the most common method of accessing the blood stream of a patient to deliver parenteral fluids into the blood stream of patients needing this type of medical treatment. Fluids in containers are allowed to flow into the patient's blood stream through tubing connected to the venipuncture needle or through a catheter that is placed into a patient's vasculature (e.g. peripheral IV, central line, etc.). During this process, fragments of incompletely sterilized skin can be delivered into the blood stream with the flow of parenteral fluids and/or at the time of venipuncture for introduction and insertion of a peripheral catheter. These fragments are undesirable in the blood stream and their introduction into the blood stream of patients (whether due to dislodging of fragments by venipuncture needle when inserting a catheter or delivered through tubing attached to needle or catheter) is contrary to common practices of antisepsis. Further, these microbes can be associated with a well-known phenomenon of colonization by skin residing organisms of the tubing and tubing connectors utilized to deliver parenteral fluids. The colonization is not typically indicative of a true infection but can give rise to false positive blood culture tests, which may result in unnecessary antibiotic treatment, laboratory tests, and replacement of the tubing apparatus with attendant patient risks and expenses. Furthermore, the risk of clinically significant serious infection due to skin residing organisms is increased.
As such, a need exists for improved fluid transfer devices, catheter introduction techniques and devices, as well as methods for delivering a parenteral fluid to a patient that reduce microbial contamination and inadvertent injection of undesirable external microbes into a patient's blood stream.